The subject matter disclosed herein relates to a system for MRI compatible communications. More specifically, a system for communication between devices within or external to an MRI scan room is disclosed.
As is known to those skilled in the art, a magnetic resonance imaging (MRI) system alternately generates a strong magnetic field and then detects the faint nuclear magnetic resonance (NMR) signals given off by nuclei in the presence of the magnetic field. The NMR signals are received by antennas, also known as coils, and transmitted to the MRI scanner for reconstruction into an MRI image. In order to provide a clear image, it is desirable to minimize electromagnetic interference from outside sources.
As a result, MRI scanners are located within a shielded room, also known as the scan room. Referring to FIG. 1, an exemplary shielded room 10 containing an MRI scanner 12 is illustrated. The scan room 10 includes walls 13, or panels, which typically incorporate the RF shielding within the wall 13. A window 15 permits an operator to observe activity within the scan room 10 from an adjacent control room 11, typically connected via a door 17. The door 17 may similarly incorporate RF shielding within the solid portion of the door. The window 15 between the scan room 10 and the control room 11 and, if present, a window in the door 17 are covered in a conductive material such as a fine wire mesh or a thin gold foil to provide RF shielding on the window. The shielding is configured to prevent external RF signals that are in a spectrum that may interfere with the MRI scanner 12 from entering the scan room 10 and causing said interference.
It is further desirable to minimize electronic components contained within the scan room 10 to prevent undesirable radiated emissions being generated. Consequently, the controller 20 for the MRI scanner 12 is typically located in the adjacent control room 11. An operator interface including, for example, a monitor 22 or other display unit and an input device such as a keyboard 24 are connected to the controller 20. The controller 20 may be connected to the MRI scanner 12 by cabling extending, for example, under the floor of the scan room 10 or in a shielded conduit to the MRI scanner 12. A penetration panel 23 in the wall may also provide connections to cables 21 running from the controller 20 into the scan room 10. The penetration panel 23 may include connectors for cabling to other medical equipment present in the scan room 10. Corresponding connectors on the other side of the penetration panel 23 within the scan room 10 permit appropriately shielded cables to be connected and run to the scanner 12 or to other medical equipment. A table 16 supports the patient being scanned and typically includes a sliding platform 19 allowing the patient to be moved into and out of the bore 14 of the MRI scanner 12.
It is typically necessary to include some additional equipment within the scan room 10. This additional equipment may be used, for example, to monitor the patient, communicate with the patient, or provide entertainment to the patient during a scan. Patients often require monitoring, for example, of heart rate, respiration, or other physiological factors. Further, acquiring images may take an extended period of time. Because the MRI operator is in the adjacent room and the patient is within the bore 14 of the MRI scanner, it may be necessary to include patient monitoring equipment within the MRI scan room 10. It may also be necessary for the MRI operator to communicate with the patient during acquisition of an image. In addition, it may be desirable to provide a distraction for the patient, such as some form of entertainment, during longer scans. Additional equipment may, therefore, be provided for monitoring and/or for communication.
When providing these additional electronic devices in the scan room, consideration must be given both to emissions from the devices interfering with the MRI scanner and emissions from the MRI scanner interfering with the devices. Often the devices include multiple components. For example, a sensor is connected to an associated recording device, a video camera includes a video cable extending to a monitor in the control room, or a video display is connected to a video storage device, such as a DVD player or a computer. Each of these devices, as well as their associated cabling, requires appropriate shielding. If the device either sends data out of or receives data in to the scan room 10, the cabling may pass through the penetration panel 23. As the number of devices in the scan room increases, the various cabling may interfere with each other or with medical personnel interacting with the patient.
Thus, it would be desirable to provide a system to wirelessly communicate with physiological sensors, patient communication systems, and/or an entertainment system that can communicate outside the shielded room without interfering with and degrading the quality of the MRI images.